A Novel Intervention Technology for Cerebral Palsy: Brain Stimulation.

A common pediatric disorder with posture and motor dysfunction in neurological diseases is known as cerebral palsy (CP). Recently, a series of effective techniques have been developed for treatment of CP. These promising methods need high-tech equipment for brain stimulation and mainly classified into invasive and no-invasive approaches. This study aimed to introduce these techniques for treatment of patients who suffer from CP. The potential and performance of currently available brain stimulation techniques have been mentioned in detail. Moreover, the clinical application, safety, efficacy and challenges of these methods have been discussed. Here we review the recent advances in the CP treatment with an emphasis on brain stimulation techniques.


Introduction
A common pediatric disorder with posture and motor dysfunction in neurological diseases is known as cerebral palsy (CP) (1)(2)(3).
Neurological disorders commonly appeared in early stage of human life statically reported about 3 to 4 cases in 1000 newborn (4, 5). These patients mainly suffer from other problems like orthopedically disorders followed by neurological dysfunctions, unfortunately, that affects their normal life (1). Around 50% of these patients show cognitive deficits.
Furthermore, one-third of children suffer from seizure attacks (6, 7). Nowadays, advanced technologies in the field of brain imaging and stimulation have been introduced to medicine for diagnosis and treatment. In addition, cellular therapy methods associated with novel advanced techniques can be useful for treating these disabilities (8-15).

REVIEW ARTICLE
Iran J Child Neurol. Spring 2019 Vol. 13 No. 2 The aim of this review is to propose effectiveness, profits, and detriments of brain stimulation techniques in CP. This paper runs over the various research efforts within this paradigm reported to date and attempts a selection of the appropriate investigation in this field that are shown in Table   1. Brain stimulation can play a role in remedying CP. Brain tissue can be directly stimulated with electricity. In these non-invasive techniques electrodes directly put in the target site in the scalp and then magnetic field created in the head using magnetic circles (9). We aimed to introduce all advanced techniques clinically used for brain stimulation in neurological disorders such as CP.
Invasive procedure for brain stimulation

Deep brain stimulation (DBS)
In this technique, precise electrical impulses directly conducted into the defect area using quad polar electrodes implanted into the brain. Electrical stimulation by this method modulates cellular functions via cell-cell signaling and communication and signaling molecules and chemical mediators.
Currently available DBS devices in the market composed of pulse generator set and two electrode leads. Pulse generator set usually fixes in subclavicular region adjusted externally and two electrode leads fix in the brain (16)(17)(18)

Direct brain Stimulation
The brain can be provoked with direct method via transcranial fascinated much attention. The past twenty years showed increasingly rapid advances in the field of rehabilitative interventions (33, 34). The direct brain stimulation (TDCS) has more effective than the other approaches for brain stimulation. This method is completely non-invasive and consists of two electrodes, one of them provokes cortical part and the other provokes inhibitory function, to stimuli brain in contact with scalp (35).
Recently an advanced model of TDCS system has been developed and showed some advantages comparing to other methods including safety, cost-effectiveness and portable, permitting neurologist to apply brain stimulation associated with exercise therapy in rehabilitation centers (36-39). The TDCS system targets the regional synaptic in the brain to control the cortical excitability. Not only local cortical stimulation induced by TDCS is not stable, but also it is The prescription of this method in CP patient is recommended for many rehabilitation centers.

Magnetic Stimulation of brain
In recent years, a novel approach has been introduced in the field of neuroscience known as transcranial magnetic stimulation (55). Abundant studies have been carried out using TMS for investigating neuroplasticity after brain injuries.
Magnetic stimulation of brain is a very simple and safe technique. Electromagnetic field is created following TMS induction in the brain tissue The repetitive TMS has been suggested in high frequency (>5-10 Hz) for treatment of stroke (68)(69)(70). Up to now, there is no evidence about any adverse symptoms for rTMS usage (71)(72)(73). The use of this advanced technique in grownups (74)(75)(76)(77) and patient with stroke are benign and acceptable (78). Both methodological and safety concern are considered as the main obstacle for using rTMS in children. Although it is more effective for movement improvement results in stroke attacks (72,73,79,80), more common disorders in pediatric, treated with rTMS technique, and are pediatric stroke and spasticity (72). The therapeutic effects were tested of the low-frequency rTMS on patient (n=10)

Acknowledgement
This study was financially supported by the grant from Iran University of Medical Sciences.